BKDR_VB.JMZ

October 08, 2012
 Analysis by: JasperM
 PLATFORM:

Windows 2000, XP, Server 2003

 OVERALL RISK RATING:
 DAMAGE POTENTIAL:
 DISTRIBUTION POTENTIAL:
 REPORTED INFECTION:

  • Threat Type: Backdoor

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

This backdoor may be dropped by other malware. It may be unknowingly downloaded by a user while visiting malicious websites.

It creates folders where it drops its files.

  TECHNICAL DETAILS

Ports:

Random TCP ports

File Size:

120,842 bytes

File Type:

PE

Memory Resident:

Yes

Initial Samples Received Date:

23 Aug 2010

Arrival Details

This backdoor may be dropped by other malware.

It may be unknowingly downloaded by a user while visiting malicious websites.

Installation

This backdoor drops the following copies of itself into the affected system:

  • %System Root%\RECYCLER\S-1-5-21-1482476501-1644491937-682003330-1013\wiseni32.exe

(Note: %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.)

It drops the following non-malicious files:

  • %System Root%\RECYCLER\S-1-5-21-1482476501-1644491937-682003330-1013\Desktop.ini
  • %Application Data%\Microsoft\Crypto\RSA\S-1-5-21-507921405-362288127-725345543-1003\a49e2717d3c2d358c0a8b3b1724ab6c9_72607dae-9d01-4c33-9a85-bc9ed0c92cf6

(Note: %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.. %Application Data% is the current user's Application Data folder, which is usually C:\Windows\Profiles\{user name}\Application Data on Windows 98 and ME, C:\WINNT\Profiles\{user name}\Application Data on Windows NT, and C:\Documents and Settings\{user name}\Local Settings\Application Data on Windows 2000, XP, and Server 2003.)

It is injected into the following processes running in memory:

  • EXPLORER.EXE

Autostart Technique

This backdoor adds the following registry entries to enable its automatic execution at every system startup:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Active Setup\Installed Components\{28ABC5C0-4FCF-11CF-ADX5-81XC1C635612}
StubPath = "%System Root%\RECYCLER\S-1-5-21-1482476501-1644491937-682003330-1013\wiseni32.exe"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Active Setup\Installed Components\{28ABC5C0-4FCF-11CF-ADX5-81XC1C635612}

Other Details

This backdoor does the following:

  • Opens random TCP ports to connect to the server f22.{BLOCKED}o.com

  SOLUTION

Minimum Scan Engine:

8.900

Step 1

For Windows XP and Windows Server 2003 users, before doing any scans, please make sure you disable System Restore to allow full scanning of your computer.

Step 2

Delete this registry key

[ Learn More ]

Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry.

  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Active Setup\Installed Components\
    • {28ABC5C0-4FCF-11CF-ADX5-81XC1C635612}

Step 3

Scan your computer with your Trend Micro product to delete files detected as BKDR_VB.JMZ. If the detected files have already been cleaned, deleted, or quarantined by your Trend Micro product, no further step is required. You may opt to simply delete the quarantined files. Please check this Knowledge Base page for more information.


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